Disposable electrode

ABSTRACT

A DISPOSABLE ELECTRODE HAVING A FOAMLIKE BASE WITH PRESSURE-SENSITIVE ADHESIVE ON ONE SURFACE, AN ANNULAR WELL PROJECTING FROM THE SURFACE ON WHICH SAID PRESSURE-SENSITIVE ADHESIVE IS LOCATED, A CONDUIT IN COMMUNICATION WITH SAID WELL FOR CONDUCTING ELECTRODE JELLY THERETO WITH AN ELECTRODE LOCATED BETWEEN SAID ANNULAR WELL AND SAID BASE, THE ELECTRODE BEING SECURED TO SAID BASED BY A LEAD WIRE WHICH EXTENDS THROUGH THE BASE AND IS BENT OVER FLAT ON THE REAR THEREOF.

United States Patent Inventor George Tatoian Williamsville, N.Y. Appl.No. 852,991 Filed Aug. 25, 1969 Patented June 28, 1971 I AssigneeCardiac Electronics, Inc.

Clarence, N.Y. Continuation of application SCI. No. 586,691, Oct. 14,1966, now abandoned.

DISPOSABLE ELECTRODE 4 Claims, 6 Drawing Figs.

U.S. Cl. l28/2.06 Int. Cl A6lh 5/04 Field of Search l28/2.06, 2.1,(Pickup Electrode Digest), 404, 4] l, 416, 4 l 7, 4 l 8 [56] ReferencesCited UNITED STATES PATENTS 2,943,627 7/ l 9 60 Howell 128/416 3,340,8689/ I967 Darling..... 128/206 3 387,608 6/1968 Figar 123/206 PrimaryExaminer-William E. Kamm Attorney-Joseph P. Gatel being secured to saidbase by a lead wire which extendsv through the as and s e ov rflatqFh?.'se.t.; .=ts2f-.,

PATENTEUJUH28|57| 3587.565

MM (291ml A ATTORNEY.

DISPOSABLE ELECTRODE This application is a continuation of applicationSer. No. 586,691, filed Oct. 14, 1966, now abandoned.

The present invention relates to an electrocardiograph accessory andmore particularly to a disposable electrode for an electrocardiographmachine.

By way of background, in order to obtain an electrocardiograph itis'necessary to place electrodes in contact with the skin of a patient.In the past, permanent electrodes were utilized which were strapped inposition. The strapping was a cumbersome and inconvenient task. Inaddition, the electrodes required frequent cleaning for sanitation andto insure good electrical contact. Disposable electrodes were relativelyexpensive and uncomfortable because of the stiffness of the backingmaterial which carried the adhesive and the stiffness of the metallicelectrode member which contacted the skin. Because of this stiffness arelatively strong adhesive was required to insure good contact which inturn caused hair to be pulled from the patient when the electrode wasremoved. Furthermore, past disposable electrodes could not confine theelectrode jelly used in conjunction therewith to an area undemeath theelectrode and this resulted in leakage which could stain the patientsclothes. It is with a disposable electrode which overcomes the foregoingshortcomings of prior devices that the present invention is concerned.

It is accordingly the primary object of the present invention to providea resilient, comfortable, easily-conforming, disposableelectrocardiograph electrode which is sufficiently soft so that apatient can lie on it without discomfort and which does not pull thepatients hair when it is removed.

Another object of the present invention is to provide a disposableelectrocardiograph electrode which includes a well for receivingelectrode jelly which not only insures good eleccialized configuration.

Still another object of the present invention is to provide an improveddisposable electrocardiograph electrode which is highly reliable andwhich can be manufactured in an extremely simple manner. Other objectsand attendant advantages of the present invention will readily beperceived hereafter.

The improved disposable electrocardiograph electrode of the presentinvention includes a base member which is both flexible and resilientand has a pressure sensitive adhesive on one side thereof. Because ofits flexibility and resiliency it can adhere satisfactorily to rough,curvedand uneven skin areas. An electrode member is provided consistingof a circular disc and a lead wire coupled thereto. The circularelectrode is located on the surface which contains pressure sensitiveadhesive and the electrical lead to the electrode extends through thebase member and is bent over on the other side thereof. The adhesive ofthe base member, which engages one side of the electrode disc, preventselectrode jelly, which is subsequently applied to the electrode, fromseeping through the base member. The lead is a normal ordinary wirethrough which any suitable lead wire from an electrocardiograph can beclamped. Special connectors are not required. Surrounding thedisc-shaped electrode member is a raised annular member which is in firmadhering engagement with the pressure sensitive adhesive on the basemember. The open central portion of the annular member provides a wellfor receiving electrode jelly and for tending to confine said jelly whenthe disposable electrode is applied to a patient. The present inventionwill be more fully understood when the following portions of thespecification are read in conjunction with the accompanying drawingwherein:

FIG. I is a perspective view of the improved disposable electrodeshowing the front surface thereof, that is, the surface which is appliedto a patient's skin;

FIG. 2 is a perspective view showing the rear surface of the improveddisposable electrode and the lead wire bent thereon;

FIG. 3 is a cross-sectional view taken substantially along line 3-3ofFIG. 2; 1

FIG. 4 is a perspective view of the electrode means which are mounted onthe disposable electrode;

FIG. 5 is a fragmentary view of an alternate embodiment of the presentinvention; and 7 FIG. 6 is a view of a still further modification of thepresent invention.

The improved disposable electrode 10 includes a base member 11 which isflexible and resilient causing it to conform easily to curved and unevenskin areas. A layer 12 of pressure sensitive adhesive comprises thefront surface of base member 11 and this layer is covered by aprotective paper covering 13 which is peeled from adhesive 12 when basemember 11 is to be applied to the patient. Base member 11 with theadhesive layer 12 and the protective paper 13 thereon can be purchasedcommercially under the trademark RESTON of the 3M Company. Base member11 is a polyurethane foam pad. However, foam rubber or any othersuitable foamlike material can be used.

An electrode member 14 (FIG. 4) consisting of a discshaped electrodemeans 15 having a lead wire 16 soldered thereto at 17 is mounted on basemember 11, after first cutting out a circular portion of backing 12 at18 to expose the pressure-sensitive adhesive 12 in this area andthereafter pushing the free end of lead wire 16 through base member 11until such time as rear surface 19 of disc 15 engages thepressuresensitive adhesive which provides good sealing engagement withthis rear surface to prevent electrode jelly which is applied to thefront surface 20 of disc 15 from leaking through the aperture formed bythe penetration of lead wire 16. Thereafter, lead wire 16, which wasoriginally straight, as

shown in FIG. 4, is bent over to the position shown in FIGS 2 g and 3 toserve the purpose of insuring that there is no separation between discmember 15 and base member 11, and also for providing a flat surfacewhich facilitates handling and packaging of disposable electrode 10. I

A raised annular member 21 which consists of a foamlike material, suchas foam rubber, is mounted on the pressuresensitive face of base member11 in concentric relationship with disc 15, with a portion of annularmember 21 overlying a peripheral portion of disc 15, as can be seen fromFIG. 3. Annular member 21 has an outside diameter which is substantiallyequal to the diameter of cutout l8. Annular member 21 has apressure-sensitive adhesive 22 of its own on the face thereof whichcontacts pressure-sensitive adhesive 12. This insures a good sealbetween annular member 21 and base member 11 and further serves toprevent leakage of electrode jelly between the two. In addition, thepressure-sensitive adhesive 22 on the inner portion of annular member 21engages the outer peripheral edge portion of disc 15 to further preventleakage (see FIG. 3). In addition, the overlap between annular member 21and disc 15 insures that said disc 15 will retain its position basemember 11, as shown in FIG. 3. Hard disc .15 will therefore remainspaced from the skin for comforth A nonadhesive plastic backing layer 23is secured to the face of annular member 21 remote from disc 15 toprevent disc face from sticking to the patients skin, thereby permittingexcess jelly. from the central portion 24 to escape to the area 25 whenthe disposable electrode 10 is placed in adhering engagement with aperson's skin. Central area 24 of annular member 21 provides a well forreceiving electrode jelly to insure good.

electrical contact between the patient's skin and electrode disc 15. I

The improved disposable electrode 10 of the present invention is used inthe following manner: Any suitable type of electrode jelly is insertedinto well 24. The well insures that a measured amount of electrode jellyis applied to the face 20 of electrode disc 15. Thereafter, backinglayer 13 is stripped from pressure-sensitive adhesive 12 by peeling ittherefrom, as shown in dotted lines in FIG. 3. The circular cutout 18surrounding annular member 21 permits backing 13 to be peeled fromadhesive 12 without removing annular member 21. Thereafter, the frontsurface containing the pressure-sensitive adhesive 12 is pressed ontothe skin area at which electrical contact is to be made. The annularmember 21 will compress slightly and also sink into the resilientmaterial of base member 11. This action produces comfortable contact,inasmuch as there is no pressing of a rigid member onto the skin. Anyexcess electrode jelly in well 24 will escape because of the fact thatcover 23 does not adhere to the skin. This excess jelly will tend toaccumulate in the area 25 surrounding annular member 21 but will notpass beyond the perimeter provided by base member 11, thereby obviatingthe tendency for staining of the patients clothes or the like.

After the disposable electrode 10 has been placed in position in theforegoing manner, any suitable type of clamp on a electrocardiographlead wire or pickup is clamped to lead wire 16 to complete theelectrical contact. Specialized contactors need not be used. After theelectrocardiograph has been taken, it is merely necessary to lift basemember 11 from the skin, and it can be thrown away.

Disc member 19 may be fabricated from any conventional material knownfor use as an electrocardiograph electrode, such as silverchloride,gennan silver, or normal silver.

In FIG. 5 a modified form of the present invention is shown, whichincludes all of the structure of the embodiments of FlGS. 1-4. Inaddition, in this embodiment a hollow tube or conduit 35 is provided forconducting electrode jelly into well 24, as by use of a suitable syringeor injector which is inserted into the end 37 of the tube which extendsbeyond the edge of member 11. Tube 35 extends through a hole in theannular wall of member 21 into well 24. The central portion of tube 35lies under protective paper 13, so that it will not interfere with theremoval of said paper. By the use of this modification the electrode canbe placed in position before jelly is conducted into well 24 throughtube 35. It is after it is in position that a suitable injector orsyringe, not shown, is inserted into tube end 37 and the proper amountofjelly is injected into well 24. With this embodiment there is no wasteofjelly. It will be appreciated that the conduit for conducting jelly tothe well may occupy a different orientation than shown, for example, itmay extend through the base member 11 into well 24.

In FIG. 6 a modified form of the electrode member construction is shown.This electrode member has a disc 15' which is identical to disc 15 shownin the preceding FlGS. However, instead of a straight lead wire shown inthe preceding FlGS., a conductive wire ring 16' which is soldered todisc 15 at 17, is used. Wire ring is inserted through a suitable slot inbase member 11, and the rear of disc 15' is caused to adhere to pressuresensitive adhesive 12, as described above relative to disc 15. The topportion of ring 16' is adjacent to the rear surface of base member 11for attachment to the clamp of a suitable electrical lead of theelectrocardiograph apparatus.

Because of the resiliency of the polyurethane foam comprising basemember 11, good adhesive contact with a patients skin is obtained,nowithstanding the curvature or irregularities thereof. Furthermore,because of the resiliency of base member 11, the pressure-sensitiveadhesive will not provide so great a bond with the hair on the person'sskin so as to cause a tearing action when the electrode is removed. Basemember 11 is approximately three-eighths inch thick, and the remainderof the elements of structure are drawn in a scale proportional to thisdimension. It will be appreciated that while a relatively thick foamlikebase member has been illustrated, sheetlike base members of othermaterials, such as plastic or fabric, can be used to support a well andelectrode if there is a willingness to sacrifice the comfort provided bya ,,foamlike base member, and this structure is within the scope ofcertain claims. While base member 11 has been depicted as rectangular,it will be appreciated that it can assume any other suitable geometricalshape. Furthermore, while disc 15 has been shown as a solid disc, it canconsist of a gridlike member to which lead wire 16 is attached, and thisstructure is included within the term disc.

It can thus be seen that the improved disposable electrocardiographelectrode of the present invention is manifestly capable of achievingthe above enumerated objects, and while a preferred embodiment of thepresent invention has been disclosed, it will be understood that it isnot limited thereto but may be otherwise embodied within the scope ofthe following claims.

I claim:

1. A disposable electrode comprising a flexible base member having asubstantially flat front surface and a rear surface, a pressuresensitive adhesive on said front surface, electrode means having a frontsurface and a substantially flat rear surface mounted on saidsubstantially flat front surface of said flexible base member, leadmeans connected to said electrode means, a well on said base memberproximate said front surface of said base member and in communicationwith said front-surface of said electrode means for receiving electrodejelly, said well being a single well formed by an annular member havinga front surface and a rear surface, said annular member being located inencircling relationship to said electrode means with said rear surfaceof said annular member being adhesively secured to said front surface ofsaid base member, said front surface of said annular member being raisedbeyond said front surface of said base member, conduit means forming apart of said disposable electrode in communication with said well forconducting electrode jelly to said well, said conduit means comprising atube lying on said front surface of said base member, a first endportion on said conduit means lying between said front surface of saidbase member and said rear surface of said annular member and extendinginto said well, and a second end portion on said conduit means remotefrom said first end portion and being located proximate the edge of saidbase member for receiving electrode jelly to be conducted to said well.

2. A disposable electrode as set forth in claim 1 wherein said leadmeans comprises a lead wire which punctures said base member and extendsthrough said flexible base member the entire distance from said frontsurface to said rear surface, said lead wire being bent over flat onsaid rear surface of said base member.

3. A disposable electrode as set forth in claim 2 wherein said electrodemeans are secured between said rear surface of said annular member andsaid front surface of said base member.

4. A disposable electrode as set forth in claim 3 wherein said basemember comprises a foamlike material for providing cushioning engagementwith said annular member.

